Math Tour - ThinkQuest 1998
A site designed to be entertaining and to bring together people of all ages with a wide range of math skills to interact and explore mathematics, featuring original math problems, humorous proofs of theorems, funny stories, and interesting facts about
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Matroid Theory - Sandra Kingan
Matroids are an abstraction of several combinatorial objects, among them graphs and matrices. The word matroid was coined by Whitney in 1935 in his landmark paper "On the abstract properties of linear dependence." In defining a matroid Whitney tried to
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Melkamu Zeleke
Melkamu Zeleke is a graduate student in combinatorics. His papers and solutions to some problems from American Mathematics Monthly and Math Magazine may be downloaded as TeX, .dvi, or PostScript files. The code for accompanying Maple packages RADON,
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New York Group Theory Cooperative at CCNY
Genetic algorithms, open problems and preprints in combinatorial and geometric group theory, meetings, links, and MAGNUS, a free (GPL) graphically oriented system, based on Tcl/Tk, for computational group theory designed to allow for exploration and experimentation
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Nim - S. J. H. Sniffen
An old, simple game between two players. A certain number of matchsticks (or stones, paper clips, etc.) are arranged in rows. The standard starting position
is the 1-3-5-7 position, in which the first row has one object, the second has three, the third
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Noga Alon
Noga Alon researches combinatorics, graph theory, their applications to theoretical computer science, combinatorial geometry and number theory, and the relationship of combinatorial algorithms and circuit complexity. Some of his papers, along with a
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The N Queens Problem - Marty Hall
Finding a solution to the N-Queens problem for any N greater than or equal to 4 can be done without searching. Determining where each queen should go can be done in constant time per queen, or O(N) altogether. Thus, drawing the board (which is O(N^2))
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The Number of Latin Rectangles [PDF] - Peter Doyle
A paper that shows how to generate an expression for the number of k-line Latin rectangles for any k. The computational complexity of the resulting expression, as measured by the number of additions and multiplications required to evaluate it, is on the
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On-line Dictionary of Combinatorics - Joe Fields
An on-line dictionary of combinatorics by a doctoral student at the University of Chicago. The dictionary is navigable by letters of the alphabet, and contains a few illustrations. Entries range from Abelian to Zorn's Lemma, and include several resources
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Open Problem Garden - Matt DeVos and Robert Šámal
A collection of unsolved problems -- mainly, graph theory, combinatorics, and number theory. A wiki for each open problem includes relevant bibliographical citations, importance rating, and recommendation for undergraduates. Navigate by math subject,
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Order - Kluwer Online
A journal on the theory of ordered sets and its applications. Order occurs throughout mathematics and especially in algebra, combinatorics, geometry, model theory, set theory and topology.
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Packomania - E. Specht
The best known packings of equal circles in the unit square and the unit circle. Tables summarize the current status of the search. Figures may be downloaded in postscript format. Also available from http://hydra.nat.uni-magdeburg.de/packing/packing.html.
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Party Games - Ivars Peterson (MathTrek)
You're one of six people at a dinner party. You would undoubtedly find that the dinner party includes either a group of at least three people who all know one another or a group of at least three people who don't know one another. The reason for this
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Pentomino - K.S.O. Glorieux Ronse, Belgium
An introduction to polyominoes, with a site-wide focus on pentominoes. The site features puzzles and contests, as well as galleries of pentomino constructions and problems, such as how to form letters of the alphabet and silhouettes of zoo animals. Available
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Philippe Flajolet
Philippe Flajolet researches the analysis of algorithms, analytic combinatorics, computer algebra, asymptotic analysis, special functions, random structures, and natural languages. An extensive collection of his articles, and the first chapters of
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Project Based Learning Pathways - David Graser
A blog about real life projects suitable for college math courses such as algebra, finite math, and business calculus. Most of these applied math projects include handouts, videos, and other resources for students, as well as a project letter. Graser,
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Puzzling Lines - Ivars Peterson (MathTrek)
Sol LeWitt has often featured geometric and combinatorial themes in his sculptures, paintings, and drawings. In 1973 he composed "Straight Lines in Four Directions and All Their Possible Combinations," a grid of 15 squares, each inscribed with one or
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The rec.puzzles Archive
The index of the rec.puzzles archive. Puzzles are categorized by subject area and include solutions compiled from various sources and supposed to be definitive. Subjects include: analysis, arithmetic, combinatorics, competition, decision, geometry, group,
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Research Institute of Symbolic Computation (RISC-Linz)
The Research Institute for Symbolic Computation, RISC, is an Austrian institute devoted to the field of symbolic computation. The site includes descriptions of various research areas, such as combinatorics, constraint solving, the theory of computation,
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Richard Stanley
Richard Stanley is a combinatorialist at the Massachusetts Institute of Technology. His site includes a complete list of his publications, PostScript files of his most recent articles, and information, including corrections, about his book Enumerative
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Sara Billey
Sara Billey researches combinatorics, algebra, Lie theory, algebraic geometry and probability. Her papers on these topics may be downloaded in PostScript or gzipped PostScript format. The syllabi and problem sets for her undergraduate courses, i.e.
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Scheduling Random Walks - Ivars Peterson (MathTrek)
Among networked computers, some sort of software scheduler must regulate data flow, but proving that a given scheduler not only prevents conflicts but also performs its duties efficiently can be surprisingly difficult. Computer scientists have found that
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The Set Game Company - Set Enterprises Inc.
SetGame is a family game of visual perception. Take the Java tutorial; learn the math behind the game (create a 3x3 magic square with SET cards, learn why the largest possible "no set" contains 20 cards, explore set theory and set operations involved
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